Dynamics of Fundamental Matter in N=2* Yang-Mills Theory

TL;DR

This paper investigates the behavior of fundamental matter in N=2* supersymmetric Yang-Mills theory using holographic D7-brane probes, revealing insights into quark dynamics, condensates, and meson spectra without spontaneous chiral symmetry breaking.

Contribution

It introduces new D7-brane embeddings in the Pilch-Warner background, analyzing their properties and effects on quark physics in the holographic dual of N=2* theory.

Findings

Identified a family of D7-brane embeddings and their properties.

Discovered a zero mass embedding ending on the enhancon without chiral symmetry breaking.

Developed a method to remove divergences in the D7-brane free energy.

Abstract

We study the dynamics of quenched fundamental matter in $\mathcal{N}=2^\ast$ supersymmetric large $N$ SU(N) Yang-Mills theory at zero temperature. Our tools for this study are probe D7-branes in the holographically dual $\mathcal{N}=2^\ast$ Pilch-Warner gravitational background. Previous work using D3-brane probes of this geometry has shown that it captures the physics of a special slice of the Coulomb branch moduli space of the gauge theory, where the $N$ constituent D3-branes form a dense one dimensional locus known as the enhancon, located deep in the infrared. Our present work shows how this physics is supplemented by the physics of dynamical flavours, revealed by the D7-branes embeddings we find. The Pilch-Warner background introduces new divergences into the D7-branes free energy, which we are able to remove with a single counterterm. We find a family of D7-brane embeddings in the geometry and discuss their properties. We study the physics of the quark condensate, constituent quark mass, and part of the meson spectrum. Notably, there is a special zero mass embedding that ends on the enhancon, which shows that while the geometry acts repulsively on the D7-branes, it does not do so in a way that produces spontaneous chiral symmetry breaking.